Estudos realizados e recomendados pela OMS e UNICEF, indicam alta prevalência de infecções pneumocócicas e meningocócicas, sobretudo em crianças abaixo dos dois anos de idade. O Streptococcus pneumoniae é um dos agentes mais frequentes de pneumonia, otite média aguda (OMA), meningite e sinusite em crianças. O número global de mortes em crianças menores de cinco anos de idade causadas por pneumonia foi de 8,8 milhões, em 2008. O Ministério da Saúde, devido ao alcance de bons resultados com soroconversão por imunização, indicou a implantação das vacinas antipneumocócica 10-valente e meningocócica C conjugadas no calendário vacinal das crianças menores de dois anos de idade. Na presente pesquisa, conduziu-se um estudo transversal com componente retrospectivo desenvolvido nas redes de Atenção Básica e Hospitalar de Guaranésia, cidade de pequeno porte do interior do estado de Minas Gerais. Objetivou-se avaliar o impacto da vacinação na ocorrência de doenças respiratórias em lactentes, considerando o período anterior e posterior à introdução da vacina antipneumocócica 10-valente, no Programa Nacional de Imunização. Na análise estatística definiu-se o período entre 2009 e 2012. O método de estudo adotado foi o um estudo transversal aninhado em uma série temporal, sendo observado que no período pós introdução da vacina antipneumocócica 10 valente conjugada houve uma redução de 40% na prevalência de pneumonia adquirida na comunidade, com diferença estatística entre os dois períodos . Confirmou-se que a oscilação sazonal tem interferência nas doenças estudadas. Em relação ao sexo, constatou-se que o masculino tem predomínio sobre o feminino quanto ao acometimento por pneumonia. Foi observado que o sexo masculino apresentou 28% mais chance de PNM. Em relação à otite média aguda e à rinossinusite, a variável sexo não apresentou predomínio entre elas. Os dados estatísticos, considerando a razão de prevalência (RP = 1,96 (IC95%: 1,52 2,53); p <0,05), sugeriram que não vacinar está associado com a ocorrência de PNM. Constatou-se que a prevalência de PNM foi 70% menor (RP 0,30 (IC95%: 0,24 0,37); p<0,05) nas crianças com vacina em dia comparando-se àquelas com a vacina em atraso, ou seja, manter vacina em dia sugere proteção contra PNM. No entanto, houve 53% menos OMA entre não vacinados do que entre vacinados (RP = 0,47 (IC95%: 0,35 0,64); p<0,05). Diante dos resultados encontrados, pode-se concluir que a vacinação antipneumocócica 10-valente está associada com redução dos casos de pneumonia adquirida na comunidade em lactentes. / Studies and recommended by WHO and UNICEF, indicate a high prevalence of pneumococcal and meningococcal infections, especially in children under two years of age. Streptococcus pneumoniae is one of the most frequent agents of pneumonia, acute otitis media (AOM), meningitis and sinusitis in children. The overall number of deaths in children under five years of age caused by pneumonia was 8.8 million in 2008. The Ministry of Health due to reach good results with seroconversion by immunization, indicated the implementation of pneumococcal vaccines 10- meningococcal C conjugate and brave in the immunization schedule of children under two years of age. In this research, conducted a cross-sectional study with retrospective component developed in primary care networks and Hospital Guaranésia, small town in the state of Minas Gerais. This study aimed to assess the impact of vaccination on the incidence of respiratory diseases in infants, considering the time before and after the introduction of the vaccine pneumococcal 10-valent, the National Immunization Program. Statistical analysis defined the period between 2009 and 2012. The adopted method of study was a cross-sectional study nested in a time series, it was observed that in the post introduction period of pneumococcal vaccine conjugate 10 brave there was a 40% reduction in the prevalence of community-acquired pneumonia, with statistical difference between the two periods. It was confirmed that the seasonal oscillation has interference in the diseases. With regard to gender, it was found that the male is predominant over females in relation to involvement by pneumonia. It was observed that men had 28% more chance of pneumonia. In relation to acute otitis media and sinusitis, sex does not showed a predominance among them. Statistical data, considering the prevalence ratio (PR = 1.96 (95% CI: 1.52 to 2.53), p <0.05), suggested that not vaccinating is associated with the occurrence of pneumonia. It was found that the prevalence of pneumonia was 70% lower (PR 0.30 (95% CI: 0.24 to 0.37), p <0.05) in children with day vaccine is compared to those of the vaccine in delay, ie to keep day suggests vaccine protection against pneumonia. However, there were 53% fewer of AOM than for unvaccinated vaccinated (OR = 0.47 (95% CI: 0.35 to 0.64); p <0.05). Considering the results, it can be concluded that vaccination pneumococcal 10-valent is associated with reduction of cases of community-acquired pneumonia in infants.

In this Thesis either advanced oxidation or reductive processes are investigated for the degradation of two pesticides considered persistent in the environment: amicarbazone (AMZ) and chlorpyrifos (CP). In chapter I, different advanced oxidation processes (AOPs) driven by sulfate (SO4o-) and hydroxyl radicals (oOH) were applied to the degradation of AMZ. In the first study, several persulfate (PS) activated reactions were explored for AMZ degradation, namely activation with UVA radiation, Fe(II) and H2O2, as well as the combination of UVA radiation with Fe(II), Fe(III) and Fe(III)-complexes. Here, the influence of different reaction variables, such as solution pH, reactants and pesticide initial concentrations, addition of a second oxidant (H2O2) and the addition of different iron catalysts were also investigated. Control experiments regarding the photolysis of iron species in the absence of PS captured our interest and, with the aim of exploring more deeply this process on AMZ degradation, a second investigation was carried out. In this second study, a Doehlert experimental design was applied to investigate the simultaneous effects of two variables on AMZ degradation: pH and Fe(III):carboxylate ratio, where the carboxylate could be oxalate, citrate or tartrate. A response surface model for the observed degradation rate (kobs) as a function of pH and Fe(III):carboxylate ratio was obtained. The processes explored in both aforementioned studies revealed to be effective for AMZ removal, although nothing is known yet about their effectiveness regarding toxicity removal. Given that, a third study was carried out, where the toxicity of AMZ solutions, before and after submission to the processes studied was evaluated towards five microorganisms: Vibrio fischeri (acute toxicity), Tetrahymena thermophile, Chlorella vulgaris (chronic toxicity), Escherichia coli and Bacilus subtilis (antimicrobial activity). The last investigation detailed in chapter I is related with the application of zero-valent-metals on PS activation, which is a subject that links this chapter with the following one. For that, zero-valent-iron (ZVI) was investigated as a PS activator and the influence of variables that help to assess the environmental applicability of this process. In general, organochlorine pesticides reveal a higher resistance to oxidation than reduction, the latter process preferred when the aim is to degrade that important class of contaminants. Therefore, in chapter II the reductive degradation of CP by means of zero-valent-metals and bimetallic particles was investigated. ZVI has been extensively applied for that purpose. However, besides iron, other zero-valent metals can be potential reactive materials for reductive degradation and hence, in this study, the effectiveness of Zn0 and Cu0 was also explored in comparison to that widely reported for ZVI. Furthermore, two different ways of enhancing metals reactivity were here explored: i) by coating ZVI or Zn0 with a more noble metal (Cu), in order to analyze the copper catalytic effect on the bimetallic system; ii) by different surface pretreatments. / Na presente Tese de Doutorado foram abordados tanto processos oxidativos avançados (POA), como processos redutivos por metais de valência zero, na degradação de dois pesticidas considerados persistentes no meio ambiente: amicarbazona (AMZ) e clorpirifós (CP). No capítulo I são apresentados os estudos realizados com diversos POA, mediados por radicais sulfato (SO4o-) e hidroxila (oOH), aplicados da AMZ. Num primeiro estudo foi explorada a ativação do oxidante persulfato (PS), de diferentes formas, tais como radiação UVA, H2O2 e Fe(II), assim como a combinação de radiação UVA com Fe(II), Fe(III) e complexos de Fe(III). Aqui também foram investigados os efeitos de diversas variáveis reacionais, tais como pH, concentração inicial de reagentes e de pesticida, adição de um segundo oxidante (H2O2) e adição de diferentes espécies de ferro. Os testes realizados, para efeito de controle, referentes à irradiação das espécies de Fe(III) na ausência de PS, despertaram o interesse para um estudo mais aprofundado sobre o efeito da fotólise destas espécies na degradação da AMZ, surgindo assim o segundo trabalho. Neste utilizou-se um projeto experimental de Doehlert, para avaliar o efeito de duas variáveis em simultâneo quanto à degradação da AMZ: pH e proporção Fe(III): ligante, sendo o ligante um dos seguintes carboxilatos: oxalato, citrato ou tartarato. Um modelo de superfície de resposta, que correlaciona a taxa de degradação observada (kobs) em função do pH e proporção Fe(III):ligante foi obtido para cada um dos complexos de Fe(III) estudados. Os processos explorados, tanto no primeiro como no segundo estudo, se mostraram eficazes na remoção da AMZ, porém nada se sabe acerca da remoção da toxicidade. Para tal, foi desenvolvido um terceiro estudo dedicado à avaliação da toxicidade da solução de AMZ, antes e após a aplicação de cada um dos processos anteriormente abordados, contra cinco micro-organismos: Vibrio fischeri (toxicidade aguda); Tetrahymena thermophila, Chlorella vulgaris (toxicidade crônica); Escherichia coli e Bacilus subtilis (atividade antimicrobiana). O último estudo abordado no capitulo I é referente à aplicação de metais de valência zero também nos POA, correlacionado assim o capítulo I e o capítulo II. Como tal, foi feito um estudo de ativação de PS por meio de ferro de valência zero (Fe0), em que se investigou a influência de diversas variáveis por forma a inferir sobre a aplicabilidade prática deste processo. Pesticidas organoclorados apresentam maior resistência à degradação por processos oxidativos do que redutivos, sendo preferível o último na degradação desta importante classe de contaminantes. Como tal, o capítulo II se refere à degradação redutiva, por meio de diferentes metais de valência zero e partículas bimetálicas, do pesticida organoclorado CP. Além do amplamente explorado Fe0, outros metais podem ser aplicados neste processo, pelo que, neste estudo, explorou-se a potencialidade de Zn0 e Cu0 comparativamente ao primeiro. Ainda neste estudo foram investigadas duas formas de aumentar a reatividade dos metais: i) no caso do Fe0 e Zn0, revestindo com um metal mais nobre (Cu), por forma a observar o efeito catalisador do último no sistema bimetálico; ii) realizando um pré-tratamento à superfície dos metais.

2,4,6-trichlorophenol (TCP) is a pervasive carcinogenic water contaminant found in a wide variety of water and waste systems and is a pertinent model compound of broader aromatic organics, specifically organo-halide pesticides. These compounds are persistent in the environment and show resilience to regular water and waste treatment protocols thus warranting the development and implementation of novel treatment materials for improved contaminant removal. Zero-valent iron (ZVI) has demonstrated the ability to remove or degrade a wide variety of inorganic and organic water contaminants, including chlorophenols, and has been widely applied for in-situ groundwater remediation where contamination is often localised in a low-oxygen environment. ZVI's broader applications in water treatment have remained mainly limited due to corrosion, particle dispersion, and confinement issues in deployment. This work, therefore, explored the development, functionality, and potential application of new modified nZVI materials (nZVI-Osorb) and assessed their potential to improve iron's intrinsic functionality while also gauging the material's viability for TCP remediation in water and waste systems. Materials produced in this thesis were prepared utilising three different embedment procedures (1-pot, multiple additions, oxygen-free). All embedment methods resulted in tightly bound composites featuring high surface areas (340.2-449.1 sq. m/g) with net iron composition ranging from 10% to 29.78% by mass. Electron imaging microscopy verified even dispersion of iron throughout the substrate. Composite materials did not exhibit a delayed rate of atmospheric corrosion over nZVI controls evincing an 18% nZVI0 loss per day until reaching a stabilised concentration (7%) after 48 hrs. nZVI-Osorb composites did produce more favourable iron oxide species which remain conducive to electron transfer from core Fe0 atom. After 50 days, a majority of nZVI in nZVI-Osorb had oxidised to maghemite (30%) and magnetite (26%) compared to control nZVI producing 19% and 12% respectively. Unreactive hematite accounted for 47% of the control and just 36% of the composite. While 1-pot embedment allowed the most substantial control over final iron composition, the oxygen-free method allowed the most reliable preservation of initial nZVI0 concentrations through restricted oxidation. Materials generated through oxygen-free embedment were utilised in the following water treatment trials with TCP. Parameters related to sorption and degradation mechanisms of TCP by nZVI-Osorb were tested in aerobic conditions, e.g. surface and potable water. nZVI-Osorb materials demonstrated high extraction capacity for TCP from aqueous solutions (Qe=1286.4 ± 13.5 mg TCP/g Osorb, Qe=1253 ± 106.7 mg TCP/g nZVI-Osorb, pH 5.1, 120mg/L TCP) and followed pseudo second order kinetics. In the broader class of chlorophenols, sorptive affinity mirrored partitioning values with highly substituted chlorophenols displaying the highest sorption capacities. Degradation of TCP by nZVI-Osorb or nZVI controls was not observed due to corrosive hindrance and inadequate reductive capacity, suggesting that materials may not be suitable for highly aerated surface and potable water treatment systems. Environmental conditions pertinent to sorption and degradation mechanisms were evaluated to improve understanding and robustness of functionality in low-oxygen applications, such as wastewater and anaerobic digesters, where nZVI-Osorb treatment is anticipated to be advantageous to TCP sorption and methane production. pH was found to influence sorption dramatically. Acidic solutions below 5 found sorption > 90%. This capacity was reduced to < 30% when pH was raised above TCP pKa value (6.23) to 7 and above. Further trials found a positive effect on TCP sorption (+7.55%) linked to net pH reduction (5.1 to 3.3) with the addition of secondary acids (volatile fatty acids: acetic, propionic, butyric, 3x 100mg/L) commonly found in anaerobic digester systems. Salinity did not affect TCP sorption. The removal of dissolved and atmospheric oxygen increased total sorption (40ppm-+1.94%, 100ppm- +7.93%, 200ppm- +0.89%, 400mg/L- +14.59%) through reduced iron corrosion and the production of favorable iron oxides, but did not facilitate contaminant degradation. Biodegradation mechanisms for TCP have broadly been established, and new research has supported the improved cometabolic degradation of recalcitrant contaminants like TCP and PCP in nZVI-dosed anaerobic digesters. Model anaerobic digester systems (3.9 g/L nZVI-Osorb, 25mg/L TCP, 240 mg/L acetic, 120mg/L propionic, 120mg/L butyric acid) containing bioreactor sludge (62.5%) were observed through standard water quality diagnostics (pH, ORP, COD, head pressure) for 14 days and suggested that nZVI-Osorb did not inhibit cellular processes. Increased electron activity from iron corrosion and hydrogen gas production, increased overall pH and decreased total ORP in these AD systems. TCP degradation by-products (DCP, CP) were detected in dilute concentrations (< 0.01 mg/L) with poor recovery by LC-MS/MS. Results suggest that nZVIOsorb may be well-suited additive for AD systems. This study contributes to knowledge of the properties, functionality, and treatment mechanisms of metal-sorbent composites with a model chlorinated aromatic water contaminant in aerobic and anaerobic environments. The work identifies favourable environmental and process conditions to apply these materials in larger scale applications, particularly, anaerobic digestion and provides support for the continued refinement and improvement of nZVI based remediation systems.

Estudos realizados e recomendados pela OMS e UNICEF, indicam alta prevalência de infecções pneumocócicas e meningocócicas, sobretudo em crianças abaixo dos dois anos de idade. O Streptococcus pneumoniae é um dos agentes mais frequentes de pneumonia, otite média aguda (OMA), meningite e sinusite em crianças. O número global de mortes em crianças menores de cinco anos de idade causadas por pneumonia foi de 8,8 milhões, em 2008. O Ministério da Saúde, devido ao alcance de bons resultados com soroconversão por imunização, indicou a implantação das vacinas antipneumocócica 10-valente e meningocócica C conjugadas no calendário vacinal das crianças menores de dois anos de idade. Na presente pesquisa, conduziu-se um estudo transversal com componente retrospectivo desenvolvido nas redes de Atenção Básica e Hospitalar de Guaranésia, cidade de pequeno porte do interior do estado de Minas Gerais. Objetivou-se avaliar o impacto da vacinação na ocorrência de doenças respiratórias em lactentes, considerando o período anterior e posterior à introdução da vacina antipneumocócica 10-valente, no Programa Nacional de Imunização. Na análise estatística definiu-se o período entre 2009 e 2012. O método de estudo adotado foi o um estudo transversal aninhado em uma série temporal, sendo observado que no período pós introdução da vacina antipneumocócica 10 valente conjugada houve uma redução de 40% na prevalência de pneumonia adquirida na comunidade, com diferença estatística entre os dois períodos . Confirmou-se que a oscilação sazonal tem interferência nas doenças estudadas. Em relação ao sexo, constatou-se que o masculino tem predomínio sobre o feminino quanto ao acometimento por pneumonia. Foi observado que o sexo masculino apresentou 28% mais chance de PNM. Em relação à otite média aguda e à rinossinusite, a variável sexo não apresentou predomínio entre elas. Os dados estatísticos, considerando a razão de prevalência (RP = 1,96 (IC95%: 1,52 2,53); p <0,05), sugeriram que não vacinar está associado com a ocorrência de PNM. Constatou-se que a prevalência de PNM foi 70% menor (RP 0,30 (IC95%: 0,24 0,37); p<0,05) nas crianças com vacina em dia comparando-se àquelas com a vacina em atraso, ou seja, manter vacina em dia sugere proteção contra PNM. No entanto, houve 53% menos OMA entre não vacinados do que entre vacinados (RP = 0,47 (IC95%: 0,35 0,64); p<0,05). Diante dos resultados encontrados, pode-se concluir que a vacinação antipneumocócica 10-valente está associada com redução dos casos de pneumonia adquirida na comunidade em lactentes. / Studies and recommended by WHO and UNICEF, indicate a high prevalence of pneumococcal and meningococcal infections, especially in children under two years of age. Streptococcus pneumoniae is one of the most frequent agents of pneumonia, acute otitis media (AOM), meningitis and sinusitis in children. The overall number of deaths in children under five years of age caused by pneumonia was 8.8 million in 2008. The Ministry of Health due to reach good results with seroconversion by immunization, indicated the implementation of pneumococcal vaccines 10- meningococcal C conjugate and brave in the immunization schedule of children under two years of age. In this research, conducted a cross-sectional study with retrospective component developed in primary care networks and Hospital Guaranésia, small town in the state of Minas Gerais. This study aimed to assess the impact of vaccination on the incidence of respiratory diseases in infants, considering the time before and after the introduction of the vaccine pneumococcal 10-valent, the National Immunization Program. Statistical analysis defined the period between 2009 and 2012. The adopted method of study was a cross-sectional study nested in a time series, it was observed that in the post introduction period of pneumococcal vaccine conjugate 10 brave there was a 40% reduction in the prevalence of community-acquired pneumonia, with statistical difference between the two periods. It was confirmed that the seasonal oscillation has interference in the diseases. With regard to gender, it was found that the male is predominant over females in relation to involvement by pneumonia. It was observed that men had 28% more chance of pneumonia. In relation to acute otitis media and sinusitis, sex does not showed a predominance among them. Statistical data, considering the prevalence ratio (PR = 1.96 (95% CI: 1.52 to 2.53), p <0.05), suggested that not vaccinating is associated with the occurrence of pneumonia. It was found that the prevalence of pneumonia was 70% lower (PR 0.30 (95% CI: 0.24 to 0.37), p <0.05) in children with day vaccine is compared to those of the vaccine in delay, ie to keep day suggests vaccine protection against pneumonia. However, there were 53% fewer of AOM than for unvaccinated vaccinated (OR = 0.47 (95% CI: 0.35 to 0.64); p <0.05). Considering the results, it can be concluded that vaccination pneumococcal 10-valent is associated with reduction of cases of community-acquired pneumonia in infants.

Highly reactive iron-oxo intermediates play important roles as active oxidants in enzymatic and synthetic catalytic oxidation. Many transition metal catalysts are designed for biomimetic studies of the predominant oxidation catalysts in Nature, namely cytochrome P450 enzymes. In this work, a series of iron(IV)-oxo porphyrins [FeIV(Por)O] and manganese(IV)-oxo porphyrins [MnIV(Por)O] have been successfully produced in two electron-deficient ligands by photochemical and chemical methods, and spectroscopically characterized by UV-vis, and 1H-NMR. With iodobenzene diacetate [PhI(OAc)2] as the oxygen source, iron(III) porphyrin and manganese(III) porphyrin complexes converted to the corresponding metal(IV)-oxo species as oxygen atom transfer (OAT) agents. In addition, a new photochemical method was developed to generate the same species by visible light irradiation of highly photo-labile porphyrin-iron(III) bromate or porphyrin-manganese(III) chlorate precursors. Furthermore, the kinetics of oxygen transfer atom reactions with alkene, active hydrocarbons and aryl sulfides by photo-generated and chemical-generated [FeIV(Por)O]were studied in CH3CN solutions. Apparent second-order rate constants determined under pseudo-first-order conditions for sulfide oxidation reactions are (9.8 ± 0.1) × 102 − (3.7 ± 0.3) × 101 M-1s-1, which are 3 to 4 orders of magnitude greater in comparison with those of alkene epoxidations and activated C-H bond oxidations by the same oxo species.

The use of nano zerovalent iron (nZVI) for environmental remediation is a promising new technique for in situ remediation. Due to its high surface area and high reactivity, nZVI is able to dechlorinate organic contaminants and render them harmless. Limited mobility, due to fast aggregation and sedimentation of nZVI, limits the capability for source and plume remediation. Carbo-Iron is a newly developed material consisting of activated carbon particles (d50 = 0,8 µm) that are plated with nZVI particles. These particles combine the mobility of activated carbon and the reactivity of nZVI. This paper presents the rst results of the transport experiments. / Der Einsatz von elementarem Nanoeisen ist eine vielversprechende Technik zur Sanierung von Altlastenschadensfällen. Aufgrund der hohen Oberäche und der hohen Reaktivität kannn ZVI chlororganische Schadstoffe dechlorieren und zu harmlosen Substanzen umwandeln. Der Einsatz von Nanoeisen zur Quellen- und Fahnensanierung wird jedoch durch mangelnde Mobilität im Boden im eingeschränkt. Carbo-Iron ist ein neu entwickeltes Material, das aus Aktivkohlepartikeln (d50 = 0,8 µm) und nZVI besteht. Diese Partikel kombinieren die Mobilit ät von Aktivkohle mit der Reaktivität von nZVI. Dieser Artikel beschreibt erste Ergebnisse von Transportuntersuchungen.

The objective of this research was to evaluate the treatment efficiency of a nitrate-contaminated soil by combined technologies of the injection of palladized nanoiron slurry and electrokinetic remediation process. First, nanoiron was prepared by two synthesis processes based on the same chemical reduction principle yielding products of NZVI-A and NZVI-B, respectively. Then they were characterized by various methods. Micrographs of scanning electron microscopy have shown that a majority of these nanoparticles were in the range of 50-80 nm and 30-40 nm, respectively. Results of nitrogen gas adsorption-desorption show that NZVI-A and NZVI-B are mesorporous (ca. 30-40 &#x00C5;) with BET surface areas of 128 m2/g and 77 m2/g, respectively. Results of X-ray diffractometry have shown that both types of nanoiron were poor in crystallinity. Results of zeta-potential measurements indicated that NZVI-A and NZVI-B had the same isoelectric point at pH 6.0. Although NZVI-A and NZVI-B were found to be superparamagnetic, their magnetization values were low. Poly acrylic acid (PAA), an anionic dispersant, was employed for stabilizing various types of nanoiron. Then Palladium¡]ca. 1 wt% of iron¡^ was selected as catalysis to form palladized nanoiron¡]Pd/Fe¡^. Results have demonstrated that an addition of 1 vol. % of PAA during the nanoiron preparation process would result in a good stabilization of nanoiron and nanoscale Pd/Fe slurry. Batch tests were carried out to investigate the effects of pH variation on degradation of nitrate aqueous solutions. Experimental results have indicated that palladized nanoiron outperformed nanoiron in treatment of nitrate in this study. Apparently, an employment of catalyst would enhance the treatment efficiency. Further, an exponential increase of the reaction rate was found for the systems at low pH. The final stage of this study was to evaluate the treatment efficiency of combined technologies of the injection of palladized nanoiron¡]Pd/Fe¡^ slurry and electrokinetic remediation process in treating a nitrate-contaminated soil. Test conditions used were given as follows: (1) slurry injection to four different positions in the soil matrix; (2) electric potential gradient: 1 V/cm; (3) daily addition of 20 mL of palladized nanoiron (4 g/L) slurry to the injection position; and (4) reaction time: 6 days. Test results have shown that addition of palladized nanoiron slurry to the anode reservoir yielded the lowest residual nitrate concentration in soil. Namely, about 99.5% removal of nitrate from soil. On the other hand, the acidic condition of soil matrix around the anode reservoir would enhance the degradation of nitrate therein. Based on the above findings, the treatment method employed in this work was proven to be a novel and efficient one in treating nitrate contaminated soil.

The performances of current electrical energy storage systems (both batteries and electrochemical capacitors) are not capable of meeting the ever-increasing demands of emerging technologies. This is because batteries often suffer from slow power delivery, limited life-time, and long charging time whereas electrochemical capacitors suffer from low energy density. While extensive efforts have been made to the development of novel electrode materials, progress has been hindered by the lack of a profound understanding on the complex charge storage mechanism. Therefore, the main objective of this research is to develop novel electrode materials which can exhibit both high energy and power density with prolonged life-time and to gain a fundamental understanding of their charge storage mechanism. First, nanostructured, thin, and conformal coatings of transition metal oxides have been deposited onto three-dimensional porous substrates of current collectors to form composite electrodes. The structures and compositions of the oxide coatings are further altered by a controlled annealing process and characterized by electron microscopy and spectroscopy, laboratory X-ray diffraction, gas adsorption analysis, and in-situ and ex-situ synchrotron-enabled X-ray diffraction and absorption spectroscopy. The structural features have also been correlated with the electrochemical behavior of the transition metal oxides as an electrode in an electrochemical capacitor. It is found that the electrochemical performance of the composite electrodes depends sensitively on the composition, nanostructure, and morphology of the oxide coatings. When optimized, the electrodes displayed the highest energy and power density with excellent cycling life among all materials reported for electrochemical capacitors. Finally, new charge storage mechanisms have also been proposed for the novel electrode materials based on insights gained from in-situ synchrotron-based X-ray absorption spectroscopy.

Phosphorus (P) is one of the essential nutrients for living organisms; however, excess P in aquatic systems often causes environmental and ecological problems including eutrophication. Removal of P from domestic wastewater, industrial wastewater, and agricultural organic-waste systems is required to minimize loading of P to receiving water bodies. A variety of sorbents or filter materials have previously been evaluated for P removal, including natural materials, industrial byproducts, and synthetic products. Among these materials industrial byproducts were reported as most effective. However, only a few of these studies were based on field experiments. Pharmaceutically active compounds (PhACs) and acesulfame-K (an artificial sweetener) are emerging contaminants observed in wastewater. The removal of PhACs in conventional wastewater treatment systems has been studied; however, few studies on alternative treatment systems are available. Studies related to the removal of acesulfame-K are even more limited. This thesis was focused on evaluation of basic oxygen furnace slag (BOFS), a byproduct from the steel manufacturing industry, as a potential reactive media for P removal from surface water and wastewater. The removal of PhACs and acesulfame-K in wastewater treatment systems containing BOFS as a treatment component was also evaluated. The effectiveness of BOFS for removing P from lake water was evaluated in a three year pilot-scale hypolimnetic withdrawal P treatment system at Lake Wilcox, Richmond Hill, Ontario. Phosphate concentrations of the hypolimnion water ranged from 0.3 to 0.5 mg L-1. About 83-100% P was removed during the experiment. The reactive mixtures were changed each year to improve the performance of the treatment system. Elevated pH (9-12) at the effluent of the treatment system was adjusted by sparging CO2(g) to near neutral pH. Elevated Al was removed through this pH adjustment. Elevated concentrations of V were removed in a column containing 5 wt% zero valent iron (ZVI) mixed with sand (0.5 m3) at the end of the BOFS based column. Removal of P in the BOFS based media is attributed to adsorption and co-precipitation at the outer layer of BOFS. Geochemical modeling results showed supersaturation with respect to hydroxyapatite, ß-tricalciumphosphate, aragonite, and calcite. Solid phase analyzes of the BOFS based reactive media collected after completion of the year 2 experiment (spent media) through combination of scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and X-ray absorption near edge structure spectroscopy (XANES) support the presence of calcium phosphate minerals on the outer layer of the spent media. A multistep wastewater treatment experiment was carried out in an indoor facility at the Center for Alternative Wastewater Treatment, Fleming College, Lindsay, Ontario, Canada. This experiment evaluated the removal of P, ammonia, cBOD5, COD, E. coli, total coliform, and trace metals in a series of treatment cells including a mixing cell, a vertical subsurface flow aerobic cell, a vertical subsurface flow P treatment cell containing BOFS, and a horizontal subsurface flow anaerobic cell. About 97-99% removal of P, NH3, cBOD5, E. coli, and total coliform; and ~72% removal of COD were achieved in the treatment system. The mixing cell and the aerated cell reduced the concentrations of P, ammonia, cBOD5, E. coli, and total coliform significantly and the P treatment cell provided additional treatment. However, the primary objective of the P treatment cell was to reduce P concentrations to the acceptable range according to the water quality guidelines. The P treatment cell had successfully fulfilled this objective. Elevated concentration of Al and V were also observed in the P treatment cell effluent. The concentration of Al decreased to below the guideline value of 0.075 mg L-1 after introducing a pH adjustment unit between the P treatment cell and the anaerobic cell. The concentration of V was decreased in the anaerobic cell effluent. However, the effluent concentration of V was much higher than the guideline value. Geochemical speciation modeling results showed supersaturation with respect to hydroxyapatite, ß-tricalciumphosphate, aragonite and calcite along the flow path. Accumulation of P on the outer layer of the spent BOFS media was identified by energy dispersive X-ray spectroscopy (EDX). Although X-ray photoelectron spectroscopy (XPS) can provide information to a depth of 5-7 nm from the outer layer of the spent media, both Ca and P were positively identified in some of the samples. Accumulation of P at the edge of the grains of the spent media was clearly identified on the element map of polished cross-sections and corresponding FTIR spectra. The phosphate and carbonate functional groups were identified by the distribution of different vibrational frequencies through FTIR spectroscopy. The presence of calcite and hydroxyapatite were inferred based on the wave numbers assigned for these minerals in the literature. Finally, X-ray absorption near edge structure spectroscopy (XANES) on the outer layer samples from the spent BOFS media and corresponding linear combination fitting analysis indicated the presence of ß-tricalciumphosphate, hydroxyapatite, and calcium phosphate dibasic. Based on the observations from the indoor wastewater treatment experiment, a multistep demonstration-scale outdoor wastewater treatment experiment was conducted to investigate the applicability of the integration of the P treatment technology and engineered wetland technology at a relatively large scale prior to a full-scale field installation. The anaerobic treatment cell was not included in this outdoor system because this unit did not efficiently remove ammonia and metals (e.g. V) from the Cell 4 effluent in the indoor system. A 10 cm layer of zero valent iron was placed at the bottom part of the down flowing P treatment cell to address the elevated V in the P treatment cell effluent observed in the indoor system and also to treat PhACs in the effluent. More than 99% removal of P, E. coli, and total coliform; >82, >98, and >76% removal of ammonia, cBOD5, and COD were achieved in this treatment system. The effluent pH (10.88±1.47) was neutralized and the concentration of V remained < 0.006 mg L-1. The Al concentration was adjusted to <0.075 mg L-1 with the neutralization of pH. Geochemical speciation modeling results showed the supersaturation of hydroxyapatite, ß-tricalciumphosphate, octatricalciumphosphate, aragonite, and calcite. The FTIR and XANES spectra showed the presence of calcium phosphate minerals on the outer layer of the spent media. Removal of the PhACs, including caffeine, ibuprofen, carbamazepine, naproxen, and sulfamethoxazole, and acesulfame-K was monitored in the demonstration-scale outdoor wastewater treatment system, which consisted of five different treatment cells including a horizontal subsurface flow constructed wetland, a vertical subsurface flow aerated cell, a vertical subsurface flow BOFS cell, and a pH neutralization unit. Significant removal of caffeine (>75%) and ibuprofen (50-75%), and moderate removal of sulfamethoxazole and naproxen (25-50%) were observed. The removal of carbamazepine was less effective with <25% removal observed. Acesulfame-K was also persistent along the flow path with <25% removal. This study demonstrated that removal of P from lake water and wastewater in excess of 95% could be achieved using BOFS as a reactive media. Integration of this media into an engineered wetland system enhances its performance in removing nutrients and other wastewater contaminants.

Chromium (VI) is a pervasive groundwater contaminant that poses a considerable threat to human health. Remediation techniques have focused on the reduction of the highly mobile Cr(VI) to the sparingly soluble, and less toxic, Cr(III) species. Traditionally, remediation performance has been evaluated through the measurement of Cr(VI) concentrations; however, this method is both costly and time-consuming, and provides little information regarding the mechanism of Cr(VI) removal. More recently, Cr isotope analysis has been proposed as a tool for tracking Cr(VI) migration in groundwater. Redox processes have been shown to produce significant Cr isotope fractionation, where enrichment in the ⁵³Cr/⁵²Cr ratio in the remaining Cr(VI) pool is indicative of a mass-transfer process. This thesis describes laboratory batch and column experiments that evaluate the Cr isotope fractionation associated with the reduction of Cr(VI) by various materials and under various conditions. Laboratory batch experiments were conducted to characterize the isotope fractionation during Cr(VI) reduction by granular zero-valent iron (ZVI) and organic carbon (OC). A decrease in Cr(VI) concentrations was accompanied by an increase in δ⁵³Cr values for the ZVI experiments. Data were fitted to a Rayleigh-type curve, which produced a fractionation factor α = 0.9994, suggesting a sorption-dominated removal mechanism. Scanning electron microscopy (SEM), X-ray absorption near-edge structure (XANES) spectroscopy, and X-ray photoelectron spectroscopy (XPS) indicated the presence of Cr(III) on the solid material, suggesting that reduction of Cr(VI) occurred. A series of batch experiments determined that reaction rate, experimental design, and pre-treatment of the ZVI had little to no effect on the Cr isotope fractionation. The interpretation of isotope results for the organic carbon experiments was complicated by the presence of both Cr(VI) and Cr(III) co-existing in solution, suggesting that further testing is required. A laboratory column experiment was conducted to evaluate isotopic fractionation of Cr during Cr(VI) reduction by OC under saturated flow conditions. Although decreasing dissolved Cr(VI) concentrations also were accompanied by an increase in δ⁵³Cr values, the isotope ratio values did not fit a Rayleigh-type fractionation curve. Instead, the data followed a linear regression equation yielding α = 0.9979. Solid-phase analysis indicated the presence of Cr(III) on the surface of the OC. Both the results of the solid-phase Cr and isotope analyses suggest a combination of Cr(VI) reduction mechanisms, including reduction in solution, and sorption prior to reduction. The linear characteristic of the δ⁵³Cr data may reflect the contribution of transport on Cr isotope fractionation.